Getting canvas' extent coordinates using PyQGIS

Question

I'm trying get the extents of the current map canvas. CRS is 22700 BNG.

My code:

canvas = iface.mapCanvas()
print(canvas)
vLayer = iface.activeLayer()
extents = vLayer.extent()
print(extents)

Which returns

qgis._gui.QgsMapCanvas object at 0x1198c6a68

qgis._gui.QgsMapCanvas object at 0x1198c6a68

I'd like to obtain 4 numbers: xMin, xMax, yMin, yMax

score 16 · Accepted Answer · answered May 06 '15 at 19:52

16

You can get the current map canvas' extent by running this line of code in the QGIS Python Console:

iface.mapCanvas().extent().toString()

In case that you want the extent of the active layer (as your code suggests), run this:

iface.activeLayer().extent().toString()

You could also get the individual numbers like this:

e = iface.mapCanvas().extent()
e.xMaximum()
e.yMaximum()
e.xMinimum()
e.yMinimum()

answered May 06 '15 at 19:52

Germán Carrillo

Just out of curiosity. Would it be just as simple to get the coordinates of a click? – BritishSteel May 06 '15 at 20:04
1

@BritishSteel I think you'd need to subclass the QgsMapTool class to be able to listen to canvasPressEvent. See http://docs.qgis.org/testing/en/docs/pyqgis_developer_cookbook/canvas.html#writing-custom-map-tools for an example. – Germán Carrillo May 06 '15 at 20:23

1 Answers1